Release Notes

Supernova UI with updated 3-Pane window with updated folder, message list, and message display panes; updated Quick Filter, Calendar and Address Book with new Vertical View, Unified Toolbar.

New folders are now added to virtual parent folders and saved searches automatically

Thunderbird can now open external .eml files in a tab

"Move To" and "Copy To" actions added to Folder context menu

Thunderbird now supports HKP keyservers that return one key per email address

Thunderbird can now upload OpenPGP public keys to VKS and HKP keyservers

Thunderbird now notifies the user if a message includes nested encryption, and allows viewing each encrypted part of the message

OpenPGP signature dates are now shown for signed messages

OpenPGP candidate keys can now be discovered and imported from GnuPG keyring, if external GnuPG is enabled

Candidate OpenPGP keys are now automatically discovered from GnuPG keyring, if external GnuPG is enabled

Thunderbird now supports option to always send public key with autocrypt header

Automatic enabling/disabling of encryption can now be enabled through UI

User-defined OpenPGP passphrases now supported

OpenPGP signature filenames now always end in ".asc"

Thunderbird can now open OpenPGP Key Manager dialog from commandline using "-keymanager" option

Using CSS styles in composer enabled; set editor.use_css to true

Thunderbird now supports OAuth2 for Fastmail

Thunderbird now includes the option to send a minimal user agent header, or no header at all

Thunderbird will now send a minimal user-agent header by default

Searching for "about:config" in Settings now finds "about:config"

Added option to always show system tray icon on Windows

Address book cards now support phone and fax number links

Thunderbird now includes a "app.update.log.file" preference to enable logging of updates

Search Engines Enterprise Policy added

Thunderbird can now individually reload remote calendars

Added "Show tasks in calendar" option to Calendar Control menu

Setting to use OS-configure timezone added

Office365 accounts using password authentication will auto-migrate to OAuth2

Thunderbird now uses a non-private browser for OAuth login, allowing login to Microsoft Office 365 with Conditional Access Policies enabled

Thunderbird now opens all external links from 3-pane window in the user's browser

HTML emails are now rendered in Standards mode

Link to "introduction to e2e encryption" article updated

OpenPGP messages now default to using combined signing and encryption

Thunderbird now displays a warning when trying to send a message if the current OpenPGP key is expired

S/MIME signatures using the MD5 or SHA1 hash algorithms are now rejected

Extension "Options" button now disabled rather than hidden when an extension is disabled or has no options

Support for additional fields added to Address Book

Search box in horizontal Address book layout moved to the left

Updated Thunderbird color palette

C++ NNTP implementation removed

POP C++ implementation removed

Thunderbird will reuse SMTP connections when sending multiple messages

Names for empty Matrix rooms can now be localized

Next and Previous Calendar menu items in Go menu now hidden until Calendar is activated

Users using Microsoft business email services may not be able to login due to deprecation of basic auth for Exchange

Spell Check dialog did not open when selected text included a line break or new paragraph

Autocomplete functionality in the composer failed under some circumstances

Some emojis displayed incorrectly when added to a message; added angry face emoji

Unicode character set information was not included in message header when composing message via "Forward" or "Edit as new message"

Forwarding messages as attachment via drag-and-drop did not follow preference to add file extension to attachment file names

Subject lines longer than the available title bar width in "New Message" window displaced title bar buttons on macOS

Opening internal document links in PDF files opened a new tab with a copy of the document instead of scrolling to the linked location

"Gentle smile" plain text ;) emoticons were incorrectly rendered as "Strong smile"/"Laugh"

Files saved via Save Attachment did not appear under Saved Files

Buttons in message header (Reply, Forward, etc) were not keyboard accessible

Drop-down buttons in message header could not be activated using Enter or Space

A "Learn More" link was missing from the "Do not track" option in "Privacy & Security" Settings

"Empty Trash on Exit" was not always triggered when message quarantine was enabled

Emails in Yahoo and AOL accounts were incorrectly classified as Junk

"Run Junk Mail Controls" did not work

HTML signature containing image hosted on a web server changed source URL of image to local filename

Changing the default search engine did not persist after closing "Settings" tab

About dialog display of distribution.ini information restored

All menu items in "Help" menu were disabled after sending a message on macOS

An empty dialog message was displayed when sending an OpenPGP signed email with a key that could not be found

When reopening OpenPGP-encrypted drafts/templates after closing the compose window, Thunderbird did not restore the subject line

OpenPGP key verification only used first From field for emails with multiple From fields

Encrypted attachment was displayed on OpenPGP encrypted messages, even if no attachment was available

When disk is full, partial data left behind by IMAP/News folder compaction was not deleted

Thunderbird did not decrypt OpenPGP messages with an additional outer signature layer

(was: old subject) was not removed from message subject on reply with OpenPGP enabled

Context menu could not be opened in OpenPGP key manager using keyboard

"Passphrase" tab of Key Manager was incorrectly shown for public keys

Upstream RNP version numbers now recognized as official in about:support

Expired OpenPGP keys were shown as "Not found" in Account Settings

Layout and styling issues with OpenPGP dialogs

Encrypted messages could not be decrypted using revoked OpenPGP key

Thunderbird no longer requires a primary secret key to be available when signing messages

Thunderbird was unable to send signed messages with OpenPGP subkey

OpenPGP Message Security dialog was sometimes positioned incorrectly

Messages signed with revoked S/MIME certificates were displayed as correctly signed

Auto-enabling and auto-disabling of E2E encryption did not behave as expected under certain circumstances

Automatic detection of SSL/TLS connections during account creation was broken

Canceling account setup during verification prevents account from being added again

Manually-configured accounts were silently deleted after pressing "Finish" on Account Setup page

Loss of messages would occur if messages were moved from POP/Local to IMAP while offline, followed by going online

POP3 messages were deleted from server when attachments were detached from the message in Thunderbird

Thunderbird sometimes did not synchronize offline IMAP folders after a restart

IMAP autosync sometimes stopped after restoring computer from sleep or hibernation

Loss of connection while moving multiple messages to an IMAP server could result in duplicate messages on source and destination servers

Thunderbird did not check to see if "UTF8=ACCEPT" is supported by IMAP server before enabling it

Copying IMAP folders between servers failed when source folder was previously copied and deleted from destination server, and destination server is set to only mark items as deleted

IMAP folder "Compact" action did not wait for expunge operation to complete prior to compaction

Progress dialog did not appear for manual retry of saving IMAP messages to Sent, Draft, or Template folders

Embedded images now include filename and extension in header if none is included

Messages could not be sent through some SMTP servers due to unhandled formatting of username prompt

NNTP message streaming did not work, resulting in uncaught errors

NNTP connection was not closed immediately if authentication dialog was canceled

Search on Server only returned results for articles on the server that had already been downloaded

Status bar did not update when NNTP server connected/disconnected

Adding too many terms to an Advanced Address Book Search caused the list view to overflow without scrolling, making overflowed terms inaccessible

Contact pane was not resizable when editing a contact

Creating a new contact was possible while editing an existing contact, with data loss of unsaved changes possible

Deleting or moving a contact from one address book to another did not update the list of cards

CardDAV discovery now uses preset location if MX records point to Google

Long lists of chat conversations could not be fully viewed or scrolled

Thunderbird incorrectly addressed all XMPP pings to the connected XMPP server, rather than the originator of the ping

Duplicate Matrix clients were created under certain circumstances, resulting in duplicate messages under the same account

Encryption of new Matrix direct messages was not detected correctly

Matrix direct message rooms were duplicated under certain circumstances

Events were not shown in the correct week if week start was not set to Monday

When creating a new event, the organizer was not automatically added to the event

Calendar time-of-day indicator increasingly drifted ahead of current time when staying on calendar tab without switching to other tabs

Multi-part messages could not be converted to tasks

Editing events via right click menu failed to save changes

Task previews did not show HTML formatting

Attendees in Event Summary dialog were not selectable

After restarting Thunderbird, all-day to-do tasks changed to tasks set at midnight of the same day

Calendars with a name containing a slash could not be exported without first being renamed

Extra linebreaks in Google Calendar event descriptions removed

Modifying events in locally-hosted ICS calendars sometimes led to data loss

Local calendars with custom timezone definitions unable to sync with CalDAV servers